The invention relates to a windshield wiper device for a vehicle, in particular a motor vehicle, and furthermore in particular to a pretensioning device for a windshield wiper device.
Windshield wiper devices typically have a wiper arm or wiper lever, wherein a wiper blade is moved over the windshield of a motor vehicle. The wiper blade is moved here between a first turning position and a second turning position. For this purpose, the wiper arm is connected via the drive shaft to a wiper motor. In particular on windshields having pronounced changes in curvature, the wiper blade easily loses contact with the windshield. This may result, in particular in the case of windshields having a pronounced curvature, in wiping areas not being wiped or in smearing.
Since a wiping operation has to be optimized for a multiplicity of parameters, such as, for example, the amount of rain falling on the windshield, a possible snow loading occurring on the windshield, the speed of the vehicle and associated wind pressure on the wiper arm, smearing cannot be reliably prevented in a simple manner by adaptation of the pressure of the wiper arm on the windshield. There is therefore a need for further improvement of windshield wiper devices.
There are a plurality of boundary conditions which should additionally be taken into consideration for improvement purposes. These include the outlay on production or the production costs, the material costs, but also the properties of the windshield wiper device, in particular the operation under diverse conditions and the durability under a multiplicity of conditions. It should be taken into consideration here in the case of wiper devices for vehicles that the cost pressure is constantly rising and that the vehicles may be used in a multiplicity of climatic conditions, and therefore, for example, extreme temperature values occur permanently and/or with great fluctuations.